Abstarct: Usually, the reason for creating a contraction in rivers is to reduce the cost of building bridges. At the contraction, it is important to check the flow changes and especially the flow depth because if the contraction is too large, it can cause blockage and water will flow out of the channel. The flow in rivers and channels is turbulent and in its simulation, the turbulence model has a significant impact on the results. In this research, ANSYS Fluent software was used to model the flow. This software solves the governing equations of the flow using the finite volume method and the free surface simulation is using the volume of fluid (vof) method. The turbulence models k-Ɛ standard, k-Ɛ RNG, k-Ɛ sensible, RSM, k-ω SST were used. The experimental results of Aukle (1983) were used to verify simulation.The aim of this research is to numerically calculate the flow using the mentioned turbulence models and compare their results with the Aukle laboratory results. The water surface profile is drawn in the range of 0.3 m before the contraction to the end of the contraction and the simulation results are compared with the laboratory results. The results show that the k-Ɛ RNG model is closer to the laboratory data. Finally, the flow surface profiles, velocity vectors and contours, pressure contour, turbulence kinetic energy changes contours (k), turbulence kinetic energy loss rate changes contour (ℇ), turbulence viscosity changes contour at different sections were investigated.